Landmark Registration

Register (align) functional data by detecting landmarks and warping curves so that the landmarks are mapped to common target positions.

Usage

landmark.register(
  fdataobj,
  kind = c("peak", "valley", "zero", "inflection"),
  min.prominence = 0,
  expected.count = 0
)

Arguments

fdataobj

An object of class 'fdata'.

kind

Character: landmark type to detect. One of "peak", "valley", "zero", "inflection". Default is "peak".

min.prominence

Minimum prominence for peak/valley detection. Default is 0.

expected.count

Expected number of landmarks per curve. If 0 (default), uses the minimum number detected across all curves.

Value

An object of class 'landmark.register' with components:

registered

fdata of registered curves

gammas

fdata of warping functions

landmarks

list of detected landmarks per curve

target_landmarks

common target landmark positions

fdataobj

the original input

Examples

# \donttest{
t <- seq(0, 1, length.out = 100)
X <- matrix(0, 10, 100)
for (i in 1:10) X[i, ] <- sin(2*pi*(t - i/50))
fd <- fdata(X, argvals = t)
lr <- landmark.register(fd, kind = "peak", min.prominence = 0.5)
# }